This invention relates generally to a filter structure for the fluid being used and recycled in connection with fabric and rug cleaning equipment. The prior art patents have a problem producing efficient back flow cleaning of a filter head. Such a patent is U.S. Pat. No. 4,696,075, issued Sep. 29, 1987 to Dale L. Grave. The back flow cleaning system embodied in the Grave patent fails to provide any means for uniformly distributing the flow of liquid through the entire area of the filter screen in either direction and also fails to provide means for removing air from the system.